MuscleNerd of iPhone Dev Team has just released an updated version of Redsn0w that improves iPhone 3GS 06.15.00 baseband downgrade which was originally released last month. In case you don’t already know, Redsn0w now allows iPhone 3G and iPhone 3GS users sporting iPad’s 06.15.00 baseband to downgrade back to 05.13.04 baseband with a fully working unlock and GPS.

Those of you who couldn’t get the downgrade to work last time around should be able to now with this latest release, provided that your iPhone qualifies for the downgrade.

This version covers 3 different types of NOR chips in the iPhone 3G and 3GS (the earlier version covered only the most prevalent NOR chip).

Instructions on how-to downgrade the baseband are pretty much similar to the last release, which you can follow here.

Additionally, a new “DFU IPSW” method has also been added in this release of Redsn0w. This method basically helps those who have an iPhone with either a broken or intermittent home button to enter DFU mode with a IPSW file. This new feature in Redsn0w can be accessed by navigating to: Extras –> Even More -> DFU IPSW.

We’ve gotten a lot of feedback from users who can’t launch a DFU ramdisk because their iPhone home/power buttons are broken or intermittent. We’ve added a new redsn0w feature that lets you enter DFU mode as long as your phone is healthy enough to restore to a normal, everyday IPSW. You don’t need to be already jailbroken to use this method.